A surface of simple geometry, such as a frame or flat surface, that covers a wide area, is found in many applications in daily life: A wall which acts as a barrier; a billboard or sign, which is used to deliver a message; a solar panel, which is used to collect the suns rays; an electromagnetic energy reflector, which serves to reflect light and microwave energy are examples of known surfaces. Those surfaces are constructed. They may be assembled as a permanent structure or, alternatively, as a temporary arrangement to fulfill a temporary need. Some are prefabricated at one location, moved to a different site, and then finally assembled. In each of the given examples, devices and techniques are known which are intended to facilitate the construction of the surface in a prompt and efficient manner.
Some surfaces are of a complex nature and thus impose greater demands for skill on the part of the workman who constructs it. In turn, simplified construction techniques or preassembly lowers the workman's skill requirements or, alternatively, allows the skilled person to accomplish the assembly more quickly. Another requirement alluded to previously is the prefabrication and transportation of the surface. Depending upon its ultimate size, the surface may be difficult or impossible to transport in one piece in conventional vehicles. Hence, surfaces of that character are packaged or folded down into a more compact shape for transportation in conventional vehicles. The lay person is most likely familiar with packaging techniques used in connection with the purchase of unassembled furniture. One may purchase a desk on display at the furniture store. The one delivered, however, arrives in a flat package, broken down for convenient transportation, and allows for assembly at home with the assistance of a screwdriver, screws, and quick fasteners, guided by an instruction sheet. Those who have tried understand; assembly is not as easy as it looks.
The demands for portability, easy transportation in compact form and ease of on-site assembly is especially critical in those surfaces that have electromagnetic energy reflecting properties and application as "reflectors", such as those which reflect visible light, infrared and microwave signals, particularly those reflectors intended for use in or about space vehicles deployed in the outermost regions of outer space. Those skilled in space application understand that the size of the transportation vehicle, such as that vehicle referred to as the "space shuttle", is limited. The shuttle cannot transport a fully assembled reflector, such as those used in radiometry, into deployment. Instead the reflector must be transported in a packed form, as part of an antenna, and on command is automatically extended and unfolds to cover a wide area. Both size and weight are limitations in this application and the limitations imposed must be respected.
Examples of reflectors appear in the patent literature. For additional background, one may make reference to U.S. Pat. No. 2,471,828 granted May 31, 1949 to Mautner; U.S. Pat. No. 3,354,458 granted Nov. 21, 1967 to Rottmayer; U.S. Pat. No. 3,617,113 granted Nov. 2, 1971 to Hoyer; U.S. Pat. No. 3,717,879 granted Feb. 20, 1973 to Ganssle; U.S. Pat. No. 4,115,784 granted Sept. 19, 1978 to Schwerdtfeger et al; U.S. Pat. No. 4,475,323 granted Oct. 9, 1984 to Schwartzberg et al; and to U.S. Pat. No. 4,482,900 granted Nov. 13, 1984 to Bilek et al.
One known type of reflector has many advantages. This is one assembled from hexagonal or quasi hexagonal segments. One such reflector is described in an article appearing in Astronautics and Aeronautics December 1977 entitled "An Entry for Large Space Antennas" authored by Messrs. Powell and Hibbs of the Jet Propulsion Laboratory of Cal Tech. That same article also suggests using an off axis feed parabolic antenna constructed from hexagonal segments. Thus a planar array made of hexagonal elements is bent over from the planar shape slightly through means of struts, trusses and/or braces to form a parabolic geometry. The antenna covers a wide area and is composed of many identical regular hexagon shaped panels.
Even if one may easily assemble a large surface on the ground, it is an altogether different matter doing so in the vacuous region of outer space. In this instance, the working man, an astronaut, wears a cumbersome space suit; the person cannot deal in a timely manner to assemble a large multitude of hexagonal panels for example, on the order of a 50, 100 or more panels, and the person would quickly tire due to the physical restraints imposed by the space suit. So far as is known, no large reflector of that type has been deployed in that application.
An object of the invention, thus, is to provide a new and more easily assembleable construction surface. It is an additional object of the invention to provide a stowable construction surface formed of hexagon shaped panels that is easy to assemble and requires minimal skill and physical dexterity to do so. A still further object is to provide a construction surface that is packaged in a compact form and which is easily assembled into a surface covering a wide area, without the need for the workman's significant manual intervention and customary skills. It is a still further object of the invention to provide an improved portable automatically assembleable reflector that is stowable in and transportable by existing space vehicles. It is a still additional object of my invention to provide an electromagnetic energy reflector that may be easily deployed and constructed in outer space without imposing undue physical burdens upon the astronaut. Those objects are achieved with the various structures characteristic of the invention, which are summarized briefly in the paragraph following.